Tracking the Detrital Zircon Provenance of Early Miocene Sediments in the Continental Shelf of the Northwestern South China Sea

Ce Wang,Letian Zeng,Ming Su,Yaping Lei,Xinquan Liang

doi:10.3390/min10090752

Abstract

Sediment provenance studies have become a major theme for source-to-sink systems and provide an important tool for assessing paleogeographic reconstruction, characterizing the depositional system, and predicting reservoir quality. The lower Miocene is an important stratigraphic unit for deciphering sediment evolution in the continental shelf of the northwestern South China Sea, but the provenance characteristics of this strata remain unclear. In this study, detrital zircon U-Pb geochronology and Lu-Hf isotopes from the lower Miocene Sanya Formation in the Yinggehai-Song Hong Basin were examined to study the provenance and its variation in the early Miocene. U-Pb dating of detrital zircons yielded ages ranging from Archean to Cenozoic (3313 to 39 Ma) and displayed age distributions with multiple peaks and a wide range of εHf(t) values (from −27.2 to +8.5). Multi-proxy sediment provenance analysis indicates that the Red River system was the major source for the sediments in the northern basin, with additional contribution from central Vietnam, and the Hainan played the most important role in contributing detritus to the eastern margin of the basin in the middle Miocene. This paper highlights the provenance of early Miocene sediments and contributes to paleogeographic reconstruction and reservoir evaluation.

Highlights

Tracing sediment delivery from terrigenous sources to oceanic sinks is crucial for understanding the sedimentary process at ocean margins
The provenance study of sediments provides an important tool for assessing paleogeographic reconstruction, characterizing the depositional system, and predicting reservoir quality [4,5]
The Yangtze Block is an important component of the South China Block, which is separated from the Indochina Block by the Song Ma suture to the south and bounded by the Cathaysia Block to the east (Figure 1)

Summary

Introduction

Tracing sediment delivery from terrigenous sources to oceanic sinks is crucial for understanding the sedimentary process at ocean margins. Clastic sedimentary rocks contain key information relating to their provenance and the sedimentary process and can be used to reveal source-to-sink systems during deposition [1,2,3]. The provenance study of sediments provides an important tool for assessing paleogeographic reconstruction, characterizing the depositional system, and predicting reservoir quality [4,5]. Sediment provenance studies have become a major theme for source-to-sink studies and have promoted efforts to link terrestrial and marine segments via the sediments produced, transported, and deposited within systems [6,7,8]. Geochronology applied to detrital minerals, such as zircon, apatite, monazite, rutile, and titanite, have received increased attention for their ability to provide insight into provenance, erosion, and tectonic processes [9,10].

Methods

Results

Discussion

Conclusion